A Correlation of Marl Beds with Types of Glacial Deposits

From a study of the distribution of bog marl in Minnesota, it is evident that some types of glacial deposits are more favorable for the development of marl than others. By ignoring all factors influencing the precipitation of calcium carbonate from lake waters and by taking into consideration the field relations only, as they now exist in regions where marl has accumulated, the following generalizations may be made: 1. The greatest number and also the largest deposits of marl are found in areas of coarse outwash sands and gravels. 2. In morainic areas, the sandy and stony moraines of the red drift contain a far greater number of marl deposits than the limy and clayey moraines of the young gray drift, even though the latter contains more lime. 3. Few marl deposits are found in lake basins, clayey till plains, or in areas of fine outwash sands. 4. Other conditions being favorable, high, irregular morainic topography favors the accumulation of marl.